Almost all mobile phones can access what are called WAP sites. WAP stands for Wireless Application Protocol and is a standard for accessing the Internet with wireless devices, for example mobile phones. When you are accessing a WAP site you are actually making a call and therefore cannot make or receive voice calls at the same time. Your network operator charges you for the amount of time you are connected.
A lot of the Bookmakers also offer an alternative to using WAP on your mobile. They allow you to download a piece of Java onto your phone which uses GPRS rather than WAP.
GPRS stands for General Packet Radio Service and is a radio technology that allows data transfer on mobile phones. Generally GPRS sends and receives data faster than WAP. Unlike WAP you can still make and receive calls whilst connected via GPRS. Your network operator charges you for the amount of data you send and receive and not for the amount of time you are connected. The Java alternative normally offers a smarter interface, however unlike WAP a lot of Mobile phones do not support it, so you may not be able to use it.
You cannot sign-up to the respective bookmakers via there WAP service, you will need to sign-up online via the links provided and then use your username and password to access their WAP site.